Articles | Volume 23, issue 3
https://doi.org/10.5194/bg-23-1181-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-1181-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| Highlight paper
| 
10 Feb 2026
Research article | Highlight paper |
| 10 Feb 2026
| 10 Feb 2026
An unpredictable body size response to the Permo-Triassic climate crisis
William J. Foster
CORRESPONDING AUTHOR
Department for Earth System Sciences, Universität Hamburg, Hamburg, Germany
Herwig Prinoth
Museum Ladin Ciastel de Tor, San Martin de Tor, Italy
Evelyn Kustatscher
Tirolerlandesmuseen, Department of Natural History, Innsbruck, Austria
Michael Hautmann
Department of Paleontology, University of Zürich, Zürich, Switzerland
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Editorial statement
This study provides an exceptional, high-resolution, specimen-level record of marine bivalve body-size dynamics across the Permian–Triassic mass extinction, one of the most extreme climate crises in Earth’s history. By distinguishing species- from genus-level responses, the authors show that post-extinction size reductions are driven mainly by faunal turnover and the emergence of smaller species, rather than by universal dwarfism within surviving taxa, thereby refining interpretations of the “Lilliput effect.” The identification of two distinct recovery phases highlights the complex interplay of evolutionary and environmental controls during prolonged climate stress and offers valuable context for understanding biological responses to rapid warming in the past and future.
This study provides an exceptional, high-resolution, specimen-level record of marine bivalve...
Short summary
Analysis of Permian–Triassic bivalve fossils from the Dolomites reveals that apparent size reductions reflect faunal turnover, not within-species dwarfing. The extinction eliminated most species, with smaller new species dominating the recovery. Whereas survivors showed no size body change. The subsequent size rebound occurred in two pulses: growth within survivors (late Griesbachian) and evolution of larger taxa (early Spathian), refining interpretations of the “Lilliput effect.”
Analysis of Permian–Triassic bivalve fossils from the Dolomites reveals that apparent size...
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